The complaints allege the company threatened workers and unilaterally changed work schedules and rules that cost employees money during a months-long fight for the future of the casino that continues unabated. Local 54 of the Unite-HERE union has been fighting Trump Entertainment Resorts for months over working conditions at the casino, which narrowly escaped closing in December when billionaire investor Carl Icahn put up $20 million to keep it afloat.

"These charges allege serious violations of federal labor law, and demonstrate a disregard for the rule of law and basic fairness at the Taj Mahal," said Bob McDevitt, the union's president. "They allege that managers threatened and discriminated against workers for union activity. Additionally, the charges claim the company has unilaterally changed the rules in ways that have cost our members work and pay, and have disrupted their lives."

Among the charges filed with the labor board are that the company fired a union shop steward; attempted to get a union member to spy on the union to management; tore down union literature and threw it on the floor, saying, "It's the union's fault that this place is closing," and unilaterally changed work schedules and rules.

The company declined comment. But billionaire investor Carl Icahn, who is acquiring Trump Entertainment by swapping $286 million in debt for ownership of the company, said last week the work rules are outdated and unaffordable in the current Atlantic City market, where four of the 12 casinos shut down last year.

A bankruptcy court judge in October allowed Trump Entertainment to end health insurance and pension coverage for its workers, a move the union is appealing. Icahn, who wants to shift Taj Mahal workers to insurance coverage under the Affordable Care Act, has threatened to close the casino if the union wins its appeal.

The labor board filed a brief last week in support of the union, urging the bankruptcy court judge to reverse his decision, saying it is not supported by federal labor law.

Tuesday is also the day Revel must respond to a court order temporarily putting its sale on hold while an appeal by restaurants at the former casino resort is heard.

Revel is also trying to fight off an attempt by its sole utility supplier to cut off electricity, heat and water to the building by 5 p.m. Thursday. ACR Energy Partners says it has no other way to ensure Revel will pay its bills.

Revel wants a judge to fine ACR $10 million, plus $1 million for each day the company withholds utility service. A hearing is scheduled Thursday morning for that dispute.

The former casino, which cost $2.4 billion to build, was due to be sold by Feb. 9 to a Florida developer for $95.4 million before the sale was temporarily blocked.

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